Phenanthrothiophene-Triazine Star-Shaped Discotic Liquid Crystals: Synthesis, Self-Assembly, and Stimuli-Responsive Fluorescence Properties.

Lipophilic biphenylthiophene- and phenanthrothiophene-triazine compounds, BPTTn and CPTTn, respectively, were prepared by a tandem procedure involving successive Suzuki-Miyaura coupling and Scholl cyclodehydrogenation reactions. These compounds display photoluminescence in solution and in thin film state, solvatochromism with increasing solvent's polarity, as well as acidochromism and metal ion recognition stimuli-responsive fluorescence. Protonation of BPTT10 and CPTT10 by trifluoroacetic acid results in fluorescence quenching, which is reversibly restored once treated with triethylamine (ON-OFF switch). DFT computational studies show that intramolecular charge transfer (ICT) phenomena occurs for both molecules, and reveal that protonation enhances the electron-withdrawing ability of the triazine core and reduces the band gap. This acidochromic behavior was applied to a prototype fluorescent anti-counterfeiting device. They also specifically recognize Fe3+ through coordination, and the recognition mechanism is closely related to the photoinduced electron transfer between Fe3+ and BPTT10/CPTT10. CPTTn self-assemble into columnar rectangular (Colrec) mesophase, which can be modulated by oleic acid via the formation of a hydrogen-bonded supramolecular liquid crystal hexagonal Colhex mesophase. Finally, CPTTn also form organic gels in alkanes at low critical gel concentration (3.0 mg/mL). Therefore, these star-shaped triazine molecules possess many interesting features and thus hold great promises for information processing, liquid crystal semiconductors and organogelators.

Competitive Coordination Structure Regulation in Deep Eutectic Electrolyte for Stable Zinc Batteries.

Rechargeable zinc-based batteries are finding their niche in energy storage applications where cost, safety, scalability matter, yet they are plagued by rapid performance degradation due to the lack of suitable electrolytes to stabilize Zn anode. Herein, we report a competitive coordination structure to form unique quaternary hydrated eutectic electrolyte with ligand-cation-anion cluster. Unraveled by experiment and calculation results, the competing component can enter initial primary coordination shell of Zn2+ ion, partially substituting Lewis basic eutectic ligands and reinforcing cation-anion interaction. The hydration-deficient complexes induced between competing eutectic as hydrogen bond donor-accepter and water also broaden the electrochemical window and confine free water activity. The altered coordination further leads to robust hybrid organic-inorganic enriched solid electrolyte interphase, enabling passivated surface and suppressed dendrite growth. Noticeably, stable Zn plating/stripping for 8000 cycles with high Coulombic efficiencies of 99.6 % and long cycling life of 10000 cycles for Zn-organic batteries are obtained. Even under harsh conditions (small N/P ratio, low temperature), the profits brought by the competitive eutectic electrolyte are still very prominent. This design principle leveraged by eutectic electrolytes with competitive coordination offers a new approach to improve battery performance.

Self-Transformation Strategy Toward Vanadium Dioxide Cathode For Advanced Aqueous Zinc Batteries.

In the lithium-dominated era, rechargeable Zn batteries are emerging as a competitive alternative. However, the sluggish kinetics of ion diffusion and structural destruction of cathode materials have thus far hampered the realization of future large-scale energy storage. Herein, an in situ self-transformation approach is reported to electrochemically boost the activity of a high-temperature, argon-treated VO2 (AVO) microsphere for effective Zn ion storage. The presynthesized AVO with hierarchical structure and high crystallinity allows efficient electrochemical oxidation and water insertion to induce self-phase transformation into V2 O5 ·nH2 O within the first charging process, which leads to rich active sites and fast electrochemical kinetics. Using AVO cathode, an outstanding discharge capacity of 446 mAh g-1 at 0.1 A g-1 , high rate capability of 323 mAh g-1 at 10 A g-1 and excellent cycling stability for 4000 cycles at 20 A g-1 with high capacity retention are demonstrated. Importantly, such zinc-ion batteries with phase self-transition can also perform well at high-loading, sub-zero temperature, or pouch cell conditions for practical application. This work not only paves a new route to design in situ self-transformation in energy storage devices, but also broadens the horizons of aqueous zinc-supplied cathodes.

Efficient Zn Metal Anode Enabled by O,N-Codoped Carbon Microflowers.

Zinc metal anodes show great promise for cheap and safe energy storage devices. However, it remains challenging to regulate highly efficient Zn plating/stripping under a high depth of discharge (DOD). Guided by density functional theory calculation, we here synthesized an oxygen- and nitrogen-codoped carbon superstructure as an efficient host for high-DOD Zn metal anodes through rational monomer selection, polymer self-assembly, and structure-preserved carbonization. With microscale 3D hierarchical structures, microcrystalline graphitic layers, and zincophilic heteroatom dopants, a flower-shaped carbon (Cflower) host could guide Zn nucleation and growth in a heteroepitaxial mode, affording horizontal plating with a high Coulombic efficiency (CE) and long life. As a demonstration, the Cflower-hosted Zn anode was paired with both battery and supercapacitor cathodes and delivered large capacity/capacitance, fast rates, long life, and ca. 100% CE even under a high DOD, outclassing hostless Zn-based devices. As they possess cheap, scalable, and efficient features, Cflower hosts hold the potential for practical zinc-metal-based energy devices.

Hetero-architectured core-shell NiMoO4@Ni9S8/MoS2 nanorods enabling high-performance supercapacitors.

ABSTRACT: An effective technique for improving electrochemical efficiency is to rationally design hierarchical nanostructures that completely optimize the advantages of single components and establish an interfacial effect between structures. In this study, core-shell NiMoO4@Ni9S8/MoS2 hetero-structured nanorods are prepared via a facile hydrothermal process followed by a direct sulfurization. The resulting hierarchical architecture with outer Ni9S8/MoS2 nanoflakes shell on the inner NiMoO4 core offers plentiful active sites and ample charge transfer pathways in continuous heterointerfaces. Ascribing to the porous core-shell configuration and synergistic effect of bimetal sulfides, the obtained NiMoO4@Ni9S8/MoS2 as electrode material presents an unsurpassed specific capacity of 373.4 F g-1 at 10 A g-1 and remarkable cycling performance in the 6 M KOH electrolyte. This work delivers a rational method for designing highly efficient electrodes for supercapacitors, enlightening the road of exploring low-cost materials in the energy storage domain. SUPPLEMENTARY INFORMATION: The online version contains supplementary material available at 10.1557/s43578-021-00318-y.

Occurrence and distribution of antibiotics in surface water.

The concentrations, distribution, and ecological risks of 24 typical antibiotics in Hong Kong rivers and seawater were investigated using high-performance liquid chromatography coupled with electrospray ionization tandem mass spectrometry (UHPLC-EI-MS/MS). The results showed that the select antibiotics were widely distributed in the study area. Among the target antibiotics, the detection rate of tetracyclines (TCs) was 100%, which indicated the widespread use of TCs in Hong Kong. The detection rates of sulfonamides (SAs) (57.1-100%), fluoroquinolones (FQs) (78.6-100%), roxithromycin (RTM) (50%) and novobiocin (NOV) (50%) were all above 50%. Compared with river water (7.9-114.26 ng/L, medium: 27.7 ng/L), concentrations of the most antibiotics in seawater (9.5-32.0 ng/L, medium: 13.3 ng/L) were lower; seawater concentrations were similar to those reported from other coastal cities, such as Guangzhou and Zhuhai in China, which implied that the source of marine antibiotic pollution may be the nearby rivers, and the vastness of the ocean causes environmental dilution of antibiotics. According to the ratio of the measured environmental concentration (MEC) to the predicted no-effect concentration (PNEC), ofloxacin (OFX) (average risk quotient: 1.94E-01) and ciprofloxacin (CFX) (average risk quotient: 3.53E-01) posed medium to high ecological risk in most places, whereas other antibiotics posed lower risk. In Yuen Long, where there were many livestock farms nearby, the detected concentration of antibiotics was higher, indicating that livestock wastewater may be the major reason for the increase in antibiotic levels in this area. In general, the detected concentration of antibiotics in Hong Kong was lower than that in the United States, Japan, the United Kingdom, and coastal areas of China, but the long-term existence of low concentrations of antibiotics also poses great risks. According to the risk assessment, Hong Kong should pay more attention to the use of FQs (e.g., OFX and CFX) in the future.

Silencing lncRNA Snhg6 mitigates bleomycin-induced pulmonary fibrosis in mice via miR-26a-5p/TGF-ß1-smads axis.

Idiopathic pulmonary fibrosis (IPF) is an interstitial pulmonary disease with slow onset and high mortality. Epithelial-mesenchymal transition (EMT) is a significant condition for tissue fibrosis, and lncRNA-Snhg6 (small nucleolar RNA host gene 6) is related to EMT in some cancer cells, but its role in pulmonary fibrosis remains obscure. Here, we found that TGF-ß1 and Snhg6 were up-regulated in lung tissues of BLM-induced lung fibrosis mouse, and Snhg6 expression was significantly increased in primary lung fibroblasts after BLM treatment. Snhg6 knockdown notably alleviated the pulmonary dysfunction, and the increase of fibrosis area and collagen deposition induced by BLM. MiR-26a-5p was downregulated in BLM-induced fibrotic lung tissues, and it was negatively regulated by Snhg6. Silencing Snhg6 markedly alleviated the TGF-ß1-induced increase in fibrotic marker expression, cell proliferation, migration and differentiation, as well as the nuclear transport of p-Smad2/3 by modulating miR-26a-5p expression in mouse lung fibroblasts. Moreover, overexpressing Snhg6-induced collagen accumulation and fibroblast activation in fibroblasts, which was reversed by treatment with miR-26a-5p mimic or oxymatrine (an inhibitor of TGF-ß1-Smads pathway). Interestingly, silencing Snhg6 in vivo mitigated BLM-driven pulmonary fibrosis by regulating the miR-26a-5p/TGF-ß1-Smads axis. Our data revealed that Snhg6 contributed to the process of BLM-driven lung fibrosis in mouse by modulating the miR-26a-5p/TGF-ß1-Smads axis, suggesting that Snhg6 might be a therapeutic target for lung fibrosis.

Association of lipid profiles with severity and outcome of acute ischemic stroke in patients with and without chronic kidney disease.

BACKGROUND: Contribution of lipid profiles to stroke severity and outcome was inconclusive, whether chronic kidney disease (CKD) (estimated glomerular filtration rate < 60 mL/min/1.73 m2) affects the association has not been investigated. We aim to evaluate this relationship. METHODS: A retrospective study of consecutive acute ischemic stroke patients was performed. We assessed the risk of severe stroke with the National Institutes of Health Stroke Scale (NIHSS) ≥ 5 at admission and poor outcome with the modified Rankin Scale (mRS) ≥ 3 at discharge. Multivariate stepwise logistic regression models were adopted to study interaction and independent association of lipid components with stroke severity and outcome according to lipid level quartiles by CKD stratification. RESULTS: Among the 875 included patients (mean age 64.9 years, 67.8% males), 213 (24.3%) presented with CKD. Elevated low-density lipoprotein cholesterol (LDL-C) was independently associated with severe stroke in patients with CKD (P for trend = 0.033) than in those without CKD (P for trend = 0.121). The association between the level of LDL-C and stroke severity was appreciably modified by CKD (Pinteraction = 0.013). Compared with without CKD patients in the lowest LDL-C quartile, the multivariable-adjusted risk of severe stroke increased significantly by 2.9-fold (95% CI 1.48-5.74) in patients with CKD in the highest LDL-C quartile. No significant association was observed between lipid components and early outcome in patients with and without CKD. CONCLUSION: LDL-C levels are positively associated with stroke severity in only patients with CKD, with an interactive impact of LDL-C and CKD on ischemic stroke in the acute phase.

Environmental perspective of COVID-19: Atmospheric and wastewater environment in relation to pandemic.

The pandemic of coronavirus disease 2019 (COVID-19), caused by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), is a major challenge to health systems worldwide. Recently, numbers of epidemiological studies have illustrated that climate conditions and air pollutants are associated with the COVID-19 confirmed cases worldwide. Researches also suggested that the SARS-CoV-2 could be detected in fecal and wastewater samples. These findings provided the possibility of preventing and controlling the COVID-19 pandemic from an environmental perspective. With this review, the main purpose is to summarize the relationship between the atmospheric and wastewater environment and COVID-19. In terms of the atmospheric environment, the evidence of the relationship between atmospheric environment (climate factors and air pollution) and COVID-19 is growing, but currently available data and results are various. It is necessary to comprehensively analyze their associations to provide constructive suggestions in responding to the pandemic. Recently, large numbers of studies have shown the widespread presence of this virus in wastewater and the feasibility of wastewater surveillance when the pandemic is ongoing. Therefore, there is an urgent need to clarify the occurrence and implication of viruses in wastewater and to understand the potential of wastewater-based epidemiology of pandemic. Overall, environmental perspective-based COVID-19 studies can provide new insight into pandemic prevention and control, and minimizes the economic cost for COVID-19 in areas with a large outbreak or a low economic level.

AMOTL2 restrains transforming growth factor-ß1-induced proliferation and extracellular matrix deposition of airway smooth muscle cells via the down-regulation of YAP1 activation.

Angiomotin-like 2 (AMOTL2) is a key modulator of signaling transduction and participates in the regulation of various cellular progresses under diverse physiological and pathological conditions. However, whether AMOTL2 participates in asthma pathogenesis has not been fully studied. In the present work, we studied the possible role and mechanism of AMOTL2 in regulating transforming growth factor-ß1 (TGF-ß1)-induced proliferation and extracellular matrix (ECM) deposition of airway smooth muscle (ASM) cells. Our results showed marked reductions in the abundance of AMOTL2 in TGF-ß1-stimulated ASM cells. Cellular functional investigations confirmed that the up-regulation of AMOTL2 dramatically decreased the proliferation and ECM deposition induced by TGF-ß1 in ASM cells. In contrast, the depletion of AMOTL2 exacerbated TGF-ß1-induced ASM cell proliferation and ECM deposition. Further research revealed that the overexpression of AMOTL2 restrained the activation of Yes-associated protein 1 (YAP1) in TGF-ß1-stimulated ASM cells. Moreover, the reactivation of YAP1 markedly reversed AMOTL2-mediated suppression of TGF-ß1-induced ASM cell proliferation and ECM deposition. Together, these findings suggest that AMOTL2 restrains TGF-ß1-induced proliferation and ECM deposition of ASM cells by down-regulating YAP1 activation.

Unilateral facial injection of Botulinum neurotoxin A attenuates bilateral trigeminal neuropathic pain and anxiety-like behaviors through inhibition of TLR2-mediated neuroinflammation in mice.

OBJECTIVES: In this study, we investigated the possible analgesic effects of Botulinum toxin type A (BoNT/A) on trigeminal neuralgia (TN). A modified TN mouse model was established by chronic constriction injury of the distal infraorbital nerve (dIoN-CCI) in mice, and the possible roles of microglia toll-like receptor 2 (TLR2) and neuroinflammation was investigated. METHODS: Male C57BL/6 mice were divided into 3 groups, including sham group, vehicle-treated TN group and BoNT/A-treated TN group. Bilateral mechanical pain hypersensitivity, anxiety-like and depressive-like behaviors were evaluated by using von Frey test, open field, elevated plus-maze testing, and forced swimming test in mice, respectively. The mRNA or protein expression levels of toll-like receptors (TLRs), glia activation markers and proinflammatory factors in the trigeminal nucleus caudalis (TNC) were tested by RT-qPCR, immunofluorescence and Western blotting. We also tested the pain behaviors of TN in Tlr2-/- mice. RESULTS: We found that unilateral subcutaneous injection of BoNT/A into the whisker pad on the ipsilateral side of dIoN-CCI mice significantly attenuated bilateral mechanical pain hypersensitivity and anxiety-like behaviors induced by dIoN-CCI surgery in mice. The dIoN-CCI surgery significantly up-regulated the expression of TLR2, MyD88, CD11b (a microglia marker), IL-1ß, TNF-α and IL-6 in the ipsilateral TNC in mice, and BoNT/A injection significantly inhibited the expression of these factors. Immunostaining results confirmed that BoNT/A injection significantly inhibited the microglia activation in the ipsilateral TNC in dIoN-CCI mice. TLR2 deficiency also alleviated bilateral mechanical pain hypersensitivity and the up-regulation of MyD88 expression in the TNC of dIoN-CCI mice. CONCLUSION: These results indicate that unilateral injection of BoNT/A attenuated bilateral mechanical pain hypersensitivity and anxiety-like behaviors in dIoN-CCI mice, and the analgesic effects of BoNT/A may be associated with the inhibition of TLR2-mediated neuroinflammation in the TNC.

[Effects of 5-azacytidine on DNA methylation and index components in patchouliol-type Pogostemon cablin].

This study aims to explore the relationship of DNA methylation with the contents of the index components as well as the growth and development of Pogostemon cablin. The demethylation reagent 5-azacytidine(5-azaC) was used to treat the tissue culture seedlings of patchouliol-type P. cablin. High performance liquid chromatography was employed to evaluate the changes of DNA methy-lation in P. cablin, and GC-MS to detect the contents of index components in P.cablin. The agronomic characters of P.cablin were measured using the common methods. The results showcased that DNA methylation of P.cablin was significantly reduced by 5-azaC in a concentration-dependent manner. Thirty days after treatment with 5-azaC at different concentrations, the content of patchouli alcohol changed slightly; compared with that in the control group, the content of pogostone in 50 µmol·L~(-1) and 100 µmol·L~(-1) 5-azaC groups was significantly up-regulated. The 100 µmol·L~(-1) 5-azaC group had the largest differences in contents of pogostone and patchouli alcohol compared with the control group, followed by the 50 µmol·L~(-1) 5-azaC group. Ninety days after disinhibition, the content of pogostone in the treatment group was significantly increased and the content of patchouli alcohol was significantly decreased. In addition, 5-azaC significantly inhibited the growth and development of P.cablin in a dose-dependent manner. These results indicate that DNA methylation regulates the biosynthesis of the index components in patchouliol-type P.cablin and proper demethylation can directly promote the synthesis of pogostone and indirectly affect the accumulation of patchouli alcohol.

MicroRNA-130a regulates neurological deficit and angiogenesis in rats with ischaemic stroke by targeting XIAP.

MicroRNAs (miRNAs) have already been proposed to be implicated in the development of ischaemic stroke. We aim to investigate the role of miR-130a in the neurological deficit and angiogenesis in rats with ischaemic stroke by regulating X-linked inhibitor of apoptosis protein (XIAP). Middle cerebral artery occlusion (MCAO) models were established by suture-occluded method, and MCAO rats were then treated with miR-130a mimics/inhibitors or/and altered XIAP for detection of changes of rats' neurological function, nerve damage and angiogenesis in MCAO rats. The oxygen-glucose deprivation (OGD) cellular models were established and respectively treated to determine the roles of miR-130a and XIAP in neuronal viability and apoptosis. The expression levels of miR-130a and XIAP in brain tissues of MCAO rats and OGD-treated neurons were detected. The binding site between miR-130a and XIAP was verified by luciferase activity assay. MiR-130a was overexpressed while XIAP was down-regulated in MCAO rats and OGD-treated neurons. In animal models, suppressed miR-130a improved neurological function, alleviated nerve damage and increased new vessels in brain tissues of rats with MCAO. In cellular models, miR-130a inhibition promoted neuronal viability and suppressed apoptosis. Inhibited XIAP reversed the effect of inhibited miR-130a in both MCAO rats and OGD-treated neurons. XIAP was identified as a target of miR-130a. Our study reveals that miR-130a regulates neurological deficit and angiogenesis in rats with MCAO by targeting XIAP.

Long noncoding MIAT acting as a ceRNA to sponge microRNA-204-5p to participate in cerebral microvascular endothelial cell injury after cerebral ischemia through regulating HMGB1.

This study is applied to the investigation of the long noncoding RNA myocardial infarction associated transcript's (MIAT's) role in regulating the expression of high-mobility group box 1 (HMGB1) in cerebral microvascular endothelial cell (CMEC) injury after cerebral ischemia by serving as a competitive endogenous RNA (ceRNA) to sponge microRNA-204-5p (miR-204-5p). The cerebral ischemia model of middle cerebral artery occlusion (MCAO) in rats was established by the suture method, in which rats were injected with empty plasmids and MIAT siRNA plasmids. The cerebral ischemia injury model in vitro was established through oxygen glucose deprivation (OGD) in primary cultured CMECs in rats. The cells were transfected with empty plasmids and MIAT siRNA plasmids. The MIAT/miR-204-5p/HMGB1 axis' function in damage and angiogenesis of CMECs were explored. The binding site between MIAT and miR-204-5p along with that between miR-204-5p and HMGB1 was determined. MIAT was overexpressed in MCAO rats' brain tissue and inhibited MIAT attenuated the injury of brain tissue in MCAO rats. Inhibition of MIAT promoted angiogenesis, promoted miR-204-5p expression and inhibited HMGB1 expression in brain tissue of MCAO rats. Inhibition of MIAT reduced CMEC damage, induced angiogenesis of CMECs, increased the number of surviving neurons, promoted miR-204-5p expression and inhibited HMGB1 expression in CMECs treated with OGD. MIAT promoted HMGB1 expression by competitive binding to miR-204-5p to regulate the injury of CMECs after cerebral ischemia. Our study showed that MIAT promoted HMGB1 expression by competitively binding to miR-204-5p to regulate the injury of CMECs after cerebral ischemia.

Pesticides in human milk collected from Jinhua, China: Levels, influencing factors and health risk assessment.

In China, many studies have been carried out on pesticide residues in human milk, yet all of them are on organochlorine pesticides (OCPs) and mostly focused on large, economically developed cities. In this study, 27 pesticides including OCPs, pyrethroid pesticides (PYRs) and organophosphate pesticides (OPPs) in human milk were investigated in Jinhua, an inland and medium sized city in China. Method based on QuEChERS extraction and gas chromatography-mass spectrometer (GC-MS) determination was adopted to analyze the above pesticide residues. The influencing factors as well as the health risks were also evaluated. Results show that PYRs and OPPs in human milk samples were both undetectable. Regarding OCPs, the detection rate of hexachlorobenzene (HCB), ß-hexachlorocyclohexane (ß-HCH) and p,p'-dichlorodiphenyl-dichloroethylene (p,p'-DDE) were 83.6%, 36.4% and 58.2%, respectively, and their mean value were 29.4, 32.0 and 85.2 ng/g lipid, respectively. p,p'-DDE levels in human milk was significantly (p < 0.05) related to maternal age, but no association was detected between OCPs residues and other factors (living environment, dietary habit, living style, etc.), suggesting that OCPs in human milk in Jinhua were originated from nonspecific source. All estimated daily intake of pesticides (EDIpesticides) by infants were under the guideline suggested by Food and Agriculture Organization (FAO) and China Ministry of Health (CMH). Yet 9% of EDIsHCB and 16% of EDIsHCHs exceeded the guideline recommended by Health Canada. The associations between DDE residues and the delivery way as well as HCBs residues and the birth weight were seemly significant, yet the significance disappeared when consider age or gestational age as a cofounder, indicating that OCPs residue in mother's body in Jinhua has no obvious influence on fetus development and the delivery way.

Role of XIAP gene overexpressed bone marrow mesenchymal stem cells in the treatment of cerebral injury in rats with cerebral palsy.

BACKGROUND: This study is performed to investigate the effects of adenovirus-mediated X-linked inhibitor of apoptosis protein (XIAP) overexpressed bone marrow mesenchymal stem cells (BMSCs) on brain injury in rats with cerebral palsy (CP). METHODS: Rat's BMSCs were cultured and identified. The XIAP gene of BMSCs was modified by adenovirus expression vector Ad-XIAP-GFP. The rat model of CP with ischemia and anoxia was established by ligating the left common carotid artery and anoxia for 2 h, and BMSCs were intracerebroventricularly injected to the modeled rats. The mRNA and protein expression of XIAP in brain tissue of rats in each group was detected by RT-qPCR and western blot analysis. The neurobehavioral situation, content of acetylcholine (Ach), activity of acetylcholinesterase (AchE), brain pathological injury, apoptosis of brain nerve cells and the activation of astrocytes in CP rats were determined via a series of assays. RESULTS: Rats with CP exhibited obvious abnormalities, increased Ach content, decreased AchE activity, obvious pathological damage, increased brain nerve cell apoptosis, as well as elevated activation of astrocyte. XIAP overexpressed BMSCs improved the neurobehavioral situation, decreased Ach content and increased AchE activity, attenuated brain pathological injury, inhibited apoptosis of brain nerve cells and the activation of astrocytes in CP rats. CONCLUSION: Our study demonstrates that XIAP overexpressed BMSCs can inhibit the apoptosis of brain nerve cells and the activation of astrocytes, increase AchE activity, and inhibit Ach content, so as to lower the CP caused by cerebral ischemia and hypoxia in rats.

Organophosphate flame retardants and bisphenol A in children's urine in Hong Kong: has the burden been underestimated?

The urine levels of organophosphate flame retardants (PFRs) and bisphenol A (BPA) in kindergarten children (n = 31, 4-6 years old, sampling performed in 2016) in Hong Kong were measured. The detection frequency of the target PFRs, tri(2-chloroethyl)phosphate (TCEP), tris(1,3-dichloro-2-propyl) phosphate (TDCIPP), tris(chloroisopropyl)phosphate (TCIPP), triphenyl phosphate (TPHP) and 2-ethylhexyl diphenyl phosphate (EHDPP) ranged from 52% to 84%. The 95th percentile urinary concentrations of TPHP, TDCIPP, TCIPP, EHDPP and TCEP were 1.70, 0.24, 0.03, 0.05, 0.68 and 0.03 ng/mL, respectively. The median urine level of BPA was 1.69 ng/mL, with a detection frequency of 77%. Due to the lack of metabolism information, two scenarios were used to calculate the estimated daily intake (EDI) of these compounds. Back-calculated EDIs of PFRs using the urinary excretion rates from in vivo animal data (scenario 2) were up to 2.97 µg/kg/d (TDCIPP), which was only a little less than that observed in a sample of American infants, and the reference dose (RfD), meaning that the potential health risk of TDCIPP cannot be ignored. Dust ingestion was suggested to be the major pathway of exposure to PFRs, but when the levels in dust and air particles in kindergartens in Hong Kong were used to predict EDIs, these values were nearly half as much as those predicted from urinary TDCIPP in this study. This suggested that children's PFRs burden may be underestimated when considering only PFR levels in dust or air. There is thus a need for further studies with large-scale surveys and investigation of exposure routes.

Effects of biochar on bacterial communities in a newly established landfill cover topsoil.

Recent studies revealed the benefits of applying biochar in landfill final cover soil, such as adsorbing odorous compounds and promoting microbial methane oxidation. Most of these processes are related to the soil bacterial communities. However, the effects of biochar application on the overall bacterial community in newly established landfill cover soil are not yet understood, especially in field condition. The objective of the present field study is to investigate the effects of biochar on the diversity of soil bacterial community 3 months after incubation (short-term). Landfill final cover topsoil (0.6 m) was amended with 0 (control), 5, and 10% (w/w) of biochar derived from peanut-shell and wheat straw. Soil bacterial communities were analysed using the 16S rRNA-based T-RFLP approach. Biochar application significantly (p < 0.05) increased the diversity of soil bacterial communities. The Shannon diversity index of bacterial communities in soil amended with 5 and 10% of biochar was increased from 3.34 to 3.85 and 3.92, respectively. There were four bacterial phyla recorded found at both control and amended soils, namely Actinobacteria, Bacteroidetes, Firmicutes, and Proteobacteria. In addition, Gemmatimonadetes was found only in soil amended with 10% biochar. The interactions between soil bacterial communities and measured soil parameters including moisture content, electrical conductivity, total organic matter, total nitrogen and total phosphorus were found to be statistically non-significant (p > 0.05), according to the canonical correspondence analysis (CCA). This may be due to the highly heterogeneous nature of landfill soil. Results from this study revealed that short-term biochar application already altered the soil physicochemical properties and increased the diversity of soil bacterial communities.

Antibiotic distribution, risk assessment, and microbial diversity in river water and sediment in Hong Kong.

For the past fewer years, environment antibiotic residues have got more and more attention. The occurrence and distribution of eight common antibiotics, belonging to five classes, were determined in both water and sediment of eleven rivers of Hong Kong. The target antibiotics were found to be widely distributed. Sulfamethoxazole (n.d.-79.9 ng/L), sulfadimidine (n.d.-29.9 ng/L), and ofloxacin (n.d.-75.5 ng/L) were the dominant antibiotics in river water, with detection rates of 84.6, 76.9, and 69.2%, respectively. Tetracycline (n.d.-9.8 ng/g) was the dominant antibiotic in sediment, with a detection rate of 60%. The concentrations of all antibiotics in river water of Hong Kong were lower than which in various rivers of Europe, North America and Australia, as well as the Pearl River Basin of China. All sediment sites exhibited significant bacterial diversity. Gammaproteobacteria (0.08-12.7%) and Flavobacteria (0.14-14.1%) were the dominant bacterial classes in all sediments. The bacterial compositions varied between sites; areas polluted with high levels of antibiotics had rich and highly diverse bacterial communities. The environmental risk assessment determined that the antibiotics in 73.1% of the samples posed ecological risks to algae, and two samples posed low risks to invertebrates. Ofloxacin was the main contributor of risk to aquatic organisms, while the antibiotics in 11.5% of the samples posed resistance selection risks. The occurrence and distribution of eight common antibiotics, belonging to five classes, were widely distributed in Hong Kong. Sulfamethoxazole, sulfadimidine, and ofloxacin were the dominant antibiotics in river waters, Tetracycline was the dominant antibiotic in sediment. Areas polluted with high levels of antibiotics had rich and highly diverse bacterial communities. Antibiotics in 73.1% of the samples posed ecological risks, while the antibiotics in 11.5% of the samples posed resistance selection risks.

Core-Shell-Shell Multifunctional Nanoplatform for Intracellular Tumor-Related mRNAs Imaging and Near-Infrared Light Triggered Photodynamic-Photothermal Synergistic Therapy.

A multifunctional nanoplatform, which generally integrates biosensing, imaging diagnosis, and therapeutic functions into a single nanoconstruct, has great important significance for biomedicine and nanoscience. Here, we developed a core-shell-shell multifunctional polydopamine (PDA) modified upconversion nanoplatform for intracellular tumor-related mRNAs detection and near-infrared (NIR) light triggered photodynamic and photothermal synergistic therapy (PDT-PTT). The nanoplatform was constructed by loading a silica shell on the hydrophobic upconversion nanoparticles (UCNPs) with hydrophilic photosensitizer methylene blue (MB) entrapped in it, and then modifying PDA shells through an in situ self-polymerization process, thus yielding a core-shell-shell nanoconstruct UCNP@SiO2-MB@PDA. By taking advantages of preferential binding properties of PDA for single-stranded DNA over double-stranded DNA and the excellent quenching property of PDA, a UCNP@SiO2-MB@PDA-hairpin DNA (hpDNA) nanoprobe was developed through adsorption of fluorescently labeled hpDNA on PDA shells for sensing intracellular tumor-related mRNAs and discriminating cancer cells from normal cells. In addition, the fluorescence resonance energy transfer from the upconversion fluorescence (UCF) emission at 655 nm of the UCNPs to the photosensitizer MB molecules could be employed for PDT. Moreover, due to the strong NIR absorption and high photothermal conversion efficiency of PDA, the UCF emission at 800 nm of the UCNPs could be used for PTT. We demonstrated that the UCNP@SiO2-MB@PDA irradiated with NIR light had considerable PDT-PTT effect. These results revealed that the developed multifunctional nanoplatform provided promising applications in future oncotherapy by integrating cancer diagnosis and synergistic therapy.